When the tiny tick bites, it can change your life forever, leaving you susceptible to what can be a deadly reaction to red meat.

Susan Morrison used to feel pretty comfortable in the kitchen and around the dinner table with friends and family until the allergic reactions started.

“I was actually visiting Myrtle Beach – we went out to eat and I had shrimp,” Morrison remembered. “During the night I broke out in hives. they got bigger. I thought I had a reaction to something I had eaten.”

Susan cut shellfish out of her diet, but the allergic reactions kept coming again and again. it seemed like everything she put in her mouth caused some sort of breakout. then she had the big one – one she wasn't sure she'd live to tell about.

“All at once my throat started closing and I couldn't swallow. it was like you were going to pass out right there,” Morrison said. “I panicked and said, 'OK, I'd better go see a doctor.' they did all the tests and said, 'You have no allergic reaction to seafood or shellfish.' then they looked at each other and said, 'we are going to do another test; one you'll find interesting.'”

The allergist tested Susan for beef. She had a reaction.

Beef was something she had been eating her entire life and now it was making her very sick.

“I first thought, 'this is just too bizarre,'” she said. “When they first did the testing the nurse asked, 'have you noticed a bad tick bite?' I said, 'oh my goodness, yes!' I found a seed tick and I thought it was infected because it was a large reaction.”

Those tick bites are turning into a big problem in parts of the Southeast – from Virginia, where Susan lives, to Tennessee, North Carolina, Arkansas and Missouri.

People are complaining of a sudden allergic reaction to beef, often hard to miss because the reaction happens three to six hours later.

A recent study by the University of Virginia found one common denominator in most cases was a tick bite. It's been dubbed the “alpha-gal allergy,” after alpha-gal, a carbohydrate found in red meat.

“It's probably going to change the way allergists look at allergies, particularly to foods,” said allergist Dr. Mark Schecker, who keeps an eye out for symptoms in his own practice. while he may not have diagnosed anyone yet, he says it's a matter of time. “We're seeing it spread. It's unclear why that is happening,” he says.

Researchers have come up with the tick theory. Researchers believe the alpha-gal is somehow stimulated by the tick bite inside the body, making a person develop antibodies to it. once you are exposed to alpha-gal from other sources, the antibody attacks, causing an allergic reaction.

“Some of these reactions can be quite severe, even fatal,” Schecker warned. “That part is very serious.”

The big problem is diagnosis. The tick theory is based on new research. Schecker only found out about it in the past year.

“It changes our thought process; it changes the questions we ask. It's an awareness thing,” Schecker explained. “Patients do need to come in because they will just not have these things evaluated for months and months. we don't even know how many patients are out there like that.”

Morrison says it's changed her life. She stays away from beef, pork and lamb now.

“(You) have to really worry about contamination if you go to a restaurant,” she said. “[You] have to ask if they have a separate grill for fish and beef.”

Cross-contamination could send her into anaphylactic shock again, so she also carries her own emergency kit – an EpiPen and liquid Benadryl are by her side all of the time.

The good thing is that it's treatable. while Morrison may miss a hamburger on occasion, she says it's a small price to pay.

“It doesn't matter to me,” she said. “You do what you have to do to be healthy.”

Researchers at UVA suggest the allergy may have something to do with climate. Blood samples from Boston and Scandinavia almost never reveal the alpha-gal antibodies, but samples from Virginia, North Carolina and other parts of the South do.

Schecker suspects as more people learn about the tick allergy, there will be more cases diagnosed.

Bottom line: if you have an unexplained allergic reaction, see a doctor. In some cases, they can be deadly.